Perhaps Gabe was jealous of Percy's relationship with his mother. So he took out his anger on Percy, and in the process, Percy got scars. For instance, Gabe might have thrown things at Percy in a fit of jealousy, which led to cuts and bruises that later turned into scars.
In some fanfictions, Gabe could be under the influence of an evil force. This force made him more aggressive towards Percy. The attacks were so severe that Percy ended up with scars. It could also be part of a bigger plot where Percy's scars are a symbol of his struggle against the evil that Gabe represents, and later in the story, these scars could give him some sort of power or connection to a greater force.
One possible story is that Gabe was drunk and got into a rage, attacking Percy. Percy was unable to fully defend himself, and thus got scars from the encounter.
Well, it could be that in the fanfiction, Percy gets into fights with Gabe over protecting his mother. Gabe, being the brute he is, might use a weapon or his fists, and Percy ends up with scars as a result. For example, he could try to stop Gabe from hitting his mother, and Gabe turns on him, causing injury that leaves scars.
One possible scenario is that the hunters disguise themselves as normal people and approach Gabe's place. When Gabe least expects it, they reveal their true identities and take him by surprise, saving Percy. Another could be that they use their tracking skills to find Percy's location even if Gabe has hidden him well.
Maybe Artemis sees Percy's potential. Percy has shown great courage and skill in other situations, and Artemis might recognize that he could be an important asset in the future battles against the forces of evil. So, she decides to save him from Gabe, who is a nuisance and a threat to Percy.
One reason could be to explore the darker side of Percy's life. His story is mainly about his heroics, but this could show what he endures at home. It also might be to create more depth to his character by showing how he copes with such a difficult situation.
Yes, there could be. It might show Percy's struggle against Gabe's abuse. Maybe Percy has no way to escape at first. But as the story progresses, he could find some support from his friends or discover his own strength within to fight back against the abuse, both physically and emotionally.
In the fanfiction, Artemis might use her divine powers. Maybe she creates a distraction so that Percy can escape from Gabe. For example, she could make a sudden bright light or a loud noise that confuses Gabe, giving Percy the chance to run away.
One possible plotline could be Percy struggling to hide the abuse from his friends at Camp Half - Blood while also dealing with his demigod duties. He might be constantly on edge, fearing Gabe's return or actions.
Well, Percy could experience emotional trauma. This might show up as nightmares or flashbacks in the fanfiction. He might also isolate himself from his friends and family because he feels ashamed or doesn't want to burden them with what he's been through. And his view of the world could become more cynical. He may start to see the world as a cruel place where bad things happen to good people like him.
One idea is that Triton seeing Percy's scars makes him reflect on his own role. Maybe he starts to feel guilty for not being more involved or helpful in Percy's previous struggles. So, he decides to offer his support and protection to Percy in a more meaningful way. This could involve teaching Percy some new skills or sharing some secrets of the underwater world that could help Percy in future battles.
The scars might be a symbol of Percy's loyalty. He has fought for his friends and the world, and the scars are the physical reminders of his selfless acts. In the fanfiction, when Jason sees them, he might understand Percy's true character better. Also, the scars could be a connection to Percy's past loves and losses. They might have stories related to people he cared about deeply and lost, or relationships that were strengthened through the battles that left the scars.